Beyond metabolism: towards a Dynamic Endocrine Framework for Eating Behaviour under Gender-Affirming Hormone Therapy

Eating behaviour arises from complex interactions among biological, psychological, and environmental processes, yet existing conceptual models rarely address populations undergoing intentional endocrine modulation. Gender-affirming hormone therapy (GAHT) induces sustained changes in sex steroid profiles with downstream effects on metabolic signalling pathways involved in appetite regulation, body composition, and energy balance. Despite increasing attention to the metabolic and clinical effects of GAHT, its potential contribution to eating behaviour remains insufficiently integrated into existing theoretical perspectives. This review synthesises current evidence on the endocrine, behavioural, and structural determinants of eating behaviour in transgender and gender-diverse (TGD) populations, highlighting major methodological and conceptual limitations, including the predominant focus on metabolic outcomes, limited assessment of dietary intake and eating behaviour, and lack of validated measurement tools for TGD populations. To address these gaps, we propose a Dynamic Endocrine Framework for Eating Behaviour, in which intentional endocrine modulation initiates the adaptive reorganisation of a multilevel system from which eating behaviour emerges. Within this framework, endocrine modulation interacts continuously with behavioural interpretation, structural embedding, and adaptive feedback across time rather than functioning as an isolated or predominant determinant of behavioural outcomes. Eating behaviour is thus conceptualised as an emergent, context-dependent property of a continuously evolving adaptive system. Rather than proposing new biological mechanisms, the framework integrates evidence from endocrinology, behavioural nutrition, transgender health, psychology, and food environment research, providing a theoretical foundation for future empirical studies and for more comprehensive clinical and structurally informed public health approaches to TGD populations.